Petrolatum Vaseline has been used for years in cosmetics and pharmacy for i.a. ointments and emulsions, because of the oil-binding, consistency-imparting and skin-refatting properties of the substance, which has also been used as a vehicle for skin active components.
Further, for many years it has been known to use surface treatment compositions in the manufacture of confectionery (e.g. liquorice, wine gum/jelly articles) and dried fruit (e.g. raisins, prunes, nuts) to give the products a shiny and glossy surface, to reduce the tendency of desiccation of the product as well as to prevent the individual product articles from sticking together.
It is also known to use paraffin oil and/or petrolatum for treating surfaces which get in direct contact with food products or food product ingredients, e.g. in the meat and bakery industries.
Furthermore, it is known to use mineral oil based products as a vehicle for bioactive substances and the like for application to animals and plants either directly or in the form of an emulsion.
Petrolatum is a mixture of predominantly saturated, solid and liquid hydrocarbons recovered from residues from distillation of mineral oil. Typically, the hydrocarbons consist of 5-20% n-paraffins as well as branched and cyclic, however, rarely aromatic components. Owing to this hetorogeneous composition petrolatum has a characteristic soft, amorphous structure over a wide temperature range.
Paraffin oil which is a mineral oil fraction, has been used for surface treatment of liquorice and jelly articles (e.g. wine gum), and here wax and/or petrolatum is generally added to increase the adhesion, the gloss and in particular the anti-sticking effect.
Paraffin oil has likewise been used for surface treatment of dried fruit (e.g. raisins), primarily as a gloss agent and a preservative, but also as an anti-sticking agent for raisins for industrial purposes (e.g. used for dragees, etc.). Advantageously, a wax type, typically beeswax, may additionally be added to raisins used in muesli products.
In recent years several countries have focused on limiting the use of paraffin oil and other mineral oil products in food products, cosmetics and pharmaceuticals because of health reasons.
So-called MCT oils (Medium Chain Triglycerides) and oxidation resistant glyceride oils, so-called high stability oils, have been used as a substitute for paraffin oil in surface treatment compositions for food products.
MCT oils are synthetic triglycerides made from glycerol and predominantly caprylic, captic and lauric acid in varying quantitative proportions. They are supplied i.a. under the trade name "Crodamol GTCC" by Croda Surfactants Ltd., England; under the trade name "Miglyol 810" by Huls AG, Marl, Germany; under the trade name "Neobee M-5" by Stepan Company Illinois U.S.A.; and under the trade name "Delios MCTs" by Henkel Corporation, USA.
For use in surface treatment compositions for food products the MCT oils have the following advantages:
Good oxidation stability. PA0 Liquid at room temperature. PA0 Low viscosity. PA0 Labile to hydrolysis with consequent diverging aftertaste ("soap taste"). PA0 Aggressive to certain plastics materials. PA0 May cause greasy appearance, because mixtures of MCT oils and wax types are milk white, with visible crystals, which may cause deposition of dim crystalline spots on clear packages. PA0 Good stability to oxidation and hydrolysis. PA0 Predominantly fluid at room temperature. PA0 No short chain fatty acids which might give poor taste by hydrolysis. PA0 The relatively high melting point may cause crystallization of fat on surface treated raisins, which may result in a dull tinge on the raisins. PA0 Too poor adhesion, which, on surface treated raisins, may cause separation of oil and sticking together and desiccation of the raisins.
and i.a. the following drawbacks:
Known oxidation resistant oils, which are extensively used for surface treatment of raisins, are partly liquid fractions of hardened vegetable liquid oils, (cottonseed oil, soybean oil, palm oil, rapeseed oil). They are supplied under the trade name "Durkex 500" by Loders & Croklaan, Holland; under the trade name "Akorex" by Karlshams Oils and Fats AB, Sweden; and under the trade name "Coatex 01" by Aarhus Oliefabrik A/S, Denmark.
For surface treatment of raisins these oxidation resistant oils have the following advantages:
and i.a. the following drawbacks:
In particular, U.S. Pat. No. 4,946,694 discloses a multi-step process for coating sticky fruits, such as dates, figs, candied fruits and dried fruits wherein the fruit is coated with a first composition comprising a suspension of vegetable wax in vegetable oil, for example the above-mentioned "Durkex 500", in the presence of a wetting agent, and then a second composition comprising a solution of a protein in a suitable inert, volatile solvent is added to the fruit, following which the fruit is dried.
As far as is known, oxidation resistant oils have not been used for surface treatment of liquorice and wine gum.
Chemically, natural waxes are usually mixtures of esters of long chain fatty acids and long chain fatty alcohols having a varying content of free fatty acids and alcohols as well as hydrocarbons. Vegetable waxes comprise e.g. carnauba wax, candelilla wax, shellak, liquid jojoba oil and hardened jojoba oil. Animal waxes comprise e.g. beeswax, bleached beeswax (cera alba), wool wax (lanolin) and spermaceti. Synthetic waxes are usually mixtures of esters of long chain fatty acids and fatty alcohols. Such are supplied i.a. under the trade name "Beeswax Synthetic" by Frank B. Ross Company, Inc., New Jersey, USA; under the trade name "Synthetic Candelilla" by Koster Keunen Holland BV, Holland; and under the trade name "Cetiol J 600" (synthetic jojoba oil) by Henkel KGaA, Dusseldorf, Germany.
Thus, it is generally known to use the above-mentioned liquid and partly liquid oils and mixtures of these with waxes for surface treatment of confectionery and dried fruit.
On the other hand, it cannot be seen that it has been attempted to replace petrolatum for cosmetic and pharmaceutical use by a combination of such glyceride oils and waxes.
For other applications, e.g. nougat centers, chocolate sandwich spread and liquid margarine, it is generally known to use liquid oil and a so-called structuring fat (hardstock). A structuring fat typically consists of mixtures of partly hardened and/or fully hardened fats, and/or high-melting fats or fractions thereof.
For example, U.S. Pat. No. 3,397,997 describes the use of a structuring fat (hardstock) in connection with the production of liquid shortenings. One example reports the use of a structuring fat in liquid glyceride oil in an amount of 5.40% (varying in the range 1-8% hardstock and 92-99% liquid triglyceride oil). The structuring fat consists of a mixture of hardened soybean oil having an iodine value of 8 and hardened erucic acid rich rapeseed oil having an iodine value of 8 in the ratio 3:2 (varying in the range 1:4-4:1). The two hardened fats exhibit differences in crystallization, the soy component being so-called .alpha.-crystallizing and the rape component being .alpha.'-crystallizing. U.S. Pat. No. 3,338,720 describes the use of 2.5% hardened cottonseed oil (melting point 58.degree.-60.degree. C.) as a structuring fat together with 97.5% liquid vegetable oil used as the fat phase in a liquid margarine which is cooled in a surface-scraped heat exchanger (tube cooler). DE Patent Specification No. 2 832 636 describes fat mixtures having a content of a triglyceride mixture on the basis of fatty acids having 8 and 10 carbon atoms, the weight ratio of fatty acids having. 8 carbon atoms to fatty acids having 10 carbon atoms being from 30:70 to 55:45, and an addition of 2-10% by weight of a hard fat component consisting of triglycerides of saturated fatty acids, the majority of which contains 12-24 carbon atoms, and having an iodine value not exceeding 2 for use in food products, in particular as a fat base in margarine.
It is also known that certain substances, such as e.g. partial glycerides, sorbitan fatty acid esters and lecithin, may be used as crystallization inhibiting additives in fat mixtures.